Bleaching agent and method of producing same



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S R k Patented Dec. 15, 1931 UNITED STATES PATENT OFFICE SCHA CIINOPEISACH SCHOTZ, OF LONDON, IlillQ'GLAlfl'Il) IBLEACH'ING AGENT ANDMETHOD OF. PRODUCING SAME No Drawing. Application filedDecember 15,1930, Serial No. 502:519i, and in Great Britain November '5 thetermfacid halogenides is intended to mean compounds having theformula oforganic acids with the exception that the OH group of theCOOH group isreplaced by a halogen; and includes mixtures giving rise -to acidhalogenides.

The object of the new invention is to provide a new method of preparingbleaching materials of.. this kind in which bleaching compoundsmentioned hereafter are produced direct by mixing a number ofingredients together.

Accordingto the present invention the bleaching is accomplished byintimately mixing aldehydes, susbstituted aldehydes or materialscontaining or setting free aldehydes with acid halogenides in absence ofwater and introducing said mixture, during or after the resultingreaction, into the flour or other material to be bleached. It isconvenient to employ the substances which are essential for theproduction of the bleaching compounds in proportions corresponding totheir molecular weights but this is not essential. p

In most cases it will be preferable, or even necessary, to introduce thereaction mixture I thus obtained into a finely powdered mixture of asuitable .base adapted to facilitate the reaction. The bases would bechosen according to the materials to be treated by the new compound. Inlieu of the bases in certain cases I may use salts of weak acidsdecomposed under conditions of the process, metals such as powderedzinc, magnesium, aluminium or calcium. 1

In order partly toaccelerate the reaction, partly to assist in removingany impurities there may be in the aldehyde substances or in the acidhalogenide substances and partly with a view to promoting the bleachingaction of the compound which is obtained it is advantageous to addhalogenating agents, such as phosphorus pentachloride, phosphoruspentabromide, phosphorus trichloride, phosphorus oxychloride, anhydrousaluminium chloride, thionyl chloride, bleaching powder, chloramine-T,dichloramine-T, po-. tassium chlorate, potassium perchlorate, and thelike.

Persalts may also be introduced.

To facilitate the reaction, bodies such as kieselguhr, silica gel, chinaclay, alumina, activated earths and other substances acting as catalystsor diluents may be added before, during or after the reaction. Liquiddiluents and solvents may be. added if desired provided they do notdecompose the reacting bodies or the product under the conditions ofmanufacture.

The substances are mixed together pref- 65 erably in such a manner thatatmospheric air and moisture shall not interfere with the reactingbodies and the mixture is allowed to stand for some time (depending onthe materials used, the temperature and the method of grinding)preferablywith occasional .mixing, after which the bleaching agent isready for use.

It is not necessary to wait until the reaction is complete beforeintroducing the mixture into the material to be bleached. If this courseis adopted the active principle conproceeding.

Materlals which absorb moisture such as so phosphorus pentoxide and thelike are a valvtinues to be formed while the bleachingis uable additionto absorb any trace of moisture.

Elevated temperatures assist the reaction provided the temperatures arenot high 35 enough to bring about the decomposition of any ofthebleaching agents obtained. If desired the bleaching compounds could beisolated or reduced in quantity by extraction with suitable solvents,orother known chemical means, i

The following three lists give an indication of the bodies which canbeemployed to carry out the improved method.

Aliphatic, alicyclic and aromatic aldehydes ma be used, such asacetaldehyde, propaldeby e, chloracetaldehyde, benzaldehyde, 0-, mandp-chlorobenzaldehyde, ethyl benzalde- .hyde, o -toluyl aldehyde,m-toluyl aldehyde, p-toluyl aldehyde, their homologues, substiwe 8. p ITREATMEIH I sauna OF TEXTILES & Hates,

of thionyl chloride and the process carried out as in Example 1. A goodbleacher is obtained.

tution products and combinations thereof and substances yielding same.

Aliphatic, alicyclic and aromatic acid halogenides may be employed, suchas acetyl 5 chloride, acetyl bromide, chloracetyl chloride, benzoylchloride, benzoyl bromide, benzoyl iodide, also o-toluyl-chloride,m-toluyl chloride, p-toluyl chloride, phenylacetyl chloride. As basicbodies for the purposes ofthis invention it is possible to employoxides, peroxides and hydroxides of the alkalies and alkaline earths, ofzinc or of other metals easily attacked by halogen-acids or their car\bonates, bicarbonates, sesquicarbonates or salts of other weak'acids;for example, the carbonates and bicarbonates of lithium, soda, potash,ammonia, the carbonates, the oxides, peroxides and hydroxides of lime, magnesia, zinc, cerium, thorium, their ormates,"

.Ewample5 6 parts of ortho-chlorobenzaldehyde are mixed with 6 parts ofbenzoyl chloride and introduced into a mixture of-15 parts anhydroussoda, 18 parts magnesium carbonate, and 1.12 parts sodium orthovandadate, and the process carried out as in Example .1. A powerfulbleaching compound for flour is obtained. I Y x The proportions of sodaand magnesiumcarbonate in the above examples are arbitrary and .can bevaried at will within very wide limits. 4 t

' Example6 I 5 parts of benzaldehyde are mixed with 6 acetates,benzoates, and salts'of other weak acids such as tungstic,:vanadic,molybdic andtitanicacids.

The followingexamples will serve to illusparts of benzoyl chlorideandthe solution introduced into a dry finely powdered mixture of 6'parts potassium bicarbonate, .10

parts magnesium carbonate, 8 parts sodium trate various ways of carryingoutthe prescarbonate and 1 a ,v part sodium tungstate andent lnventlonbut it is to be understood that the ingredients ground together mihetsfiope of thelmventlon isnot to be hunted miner referred to inExample 5 ese examp After 4 8 hours standing the mixture is' a Example 1ground again and heated to about 50C. until 15 parts of dehydrated sodaare mixed with 1 of e mell of benzoyl chloride has 18 parts ofdehydrated magnesium carbonate s pp df and into the mixture thusobtained are intro b An ex llent bleaching material for flour duced 5parts'of purified benzaldehyde and 6 1 flmed. parts of benzoyl chloride.The ingredients 1 are ground together at ordinary temperature withexclusion of moisture in a closed container having a suitable outletrforany gase chloride and 10 grams benzaldehyde is introformed during thereaction and allowed to duced into a dry mixture of 7.5 parts soda, 8.5stand with occasional grinding for several parts potassium bicarbonate,6.5 parts magnedays until the mell of benzoyl chloride has siumcarbonate, 1 part cerium carbonate and nearly disappeared. The product15;!- P W- thoroughly incorporated by grinding. "After dery mass whichhas good bleaching properstanding for 2 days at room temperature as tiesfor flour. in Example 1, it is heated for" 24 hours-bea tween 30e50 C.An eflicient though somewhat slow bleacher is obtained. 110

Ewample i A freshly made solution of 5 grams -acetyl Example 2 Totheconstituents mentioned in Example 1 are added 1.1 parts of sodium orthovanadate and the ingredients are mixed as in Example 1. It would seemthat the product obtained with the addition of the vanadate compound hasrather better bleachin properties 'for flour than the product o tainedwithout the addition of this vanadate comd Pound. Emm' l6 3 o p i Q 15grams kieselguhr free from iron and p 7 organic matter. r

Instead of mugiture P e When mixed with flour this material ex- Example2 ea at imp merted a distinctbleac'hing eifect.-

' P Obtamed Q g together The choice and total quantity of the inthelngredlents was heated for one and a-half gredients in each case wouldgoverned by w at abimt m contamel: of the costs, reactivity, poisonousnature, degree of naturgdescnbed m Example Avery good unpleasantne'ssease of handling hygrosco-j bleaching compound for. flourwas obtained.picitv purpose for which the praduct is Ewamllle 4. v I quired and'suchlikepractical-considerations.- Y To the 'benzaldehyde and benzoylchloride The product obtained according to'any of mentioned Example 1are added 0.5 parts the above examples should be applied to the 130Example 8- 5 grams benzaldehyde were mixed with 6 grams benzoyl chlorideand 0.6 grams of anhydrous aluminium chloride and heated for 1 hours atabout 100 C.

'After standing overnight 5 grams of: the mass obtained were intimatelymixed with substance to be bleached, for example flour, in a finelydivided condition.

I am awarethat it has previousl I been proposed in'connection with thedeco ourizing of woven cotton fabrics to employ mono- Ibenzylparasulphochloride with the addition of sodiumhydrosulphite-formaldehyde along with the usual liquors or lyes of milkof lime or the like, together with other suitable com- 10 pounds such asanthraquinones.

Having now particularly described and ascertained the nature of my saidinvention and in what manner the same is to be performed I declarethatwhat I claimis:

15 1. Method of producing bleaching agents for flour and other millingproducts, con- 9 sisting in forming a dry mixture of alde-. .hydes andacid halogenides, intimately mixing these constituents with basic bodiesand :0 adding to the mixture halogenating agents and persalts.

2. Method of producing bleaching agents for flour and other millingproducts, consistin in forming a dry mixture of substituted aldehydesand acid halogenides, intimately mixing these constituents with basicbodies and adding to the mixture halogenating agents. Q

Method of producing bleaching agents :0 for flour and other millingproducts, consisting in forming a dry mixture of substituted aldehydesand acid halogenides, intimately mixing these constituents with basicbodies and adding to the mixture persalts.

at. 4. Method of producing bleaching agents for flour and other millingproducts, consist- ,ing in forming a dry mixture of aldehydes and acidhalogenides, intimately mixing these constituents with basic bodies,adding 40 halogenating agents and adding bodies such as kieselguhr,silica gel, china clay, alumina and activated earths. 1

5. Method of producing bleaching agents for flour and other millingproducts,consi sting in forming a'dry mixture of benzaldehyde andbenzoyl chloride, intimately mix ing these constitueiits with magnesiumcarbonate and adding thereto sodium ortho vanadate.

5 6. Method of producing bleaching agents, 1

I for flour and-other milling products, consisting in forming a drymixture of benzaldehyde and benzoyl chloride-,and intimately mixingthese constituents with a carbonate 55 of a metal selected from the;group consistin of the alkali and alkali earth metals.

A method of producing I bleaching agents for flour and othei\ millingproducts consisting of forming a dry mixture of alde-- co hyde and acidhalogenides,.and; intimately mixing these constituents with a carbonatel of a metal selected from the 'groupconsisting of the alkali and alkaliearth metals;

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